libgui/SF: Fix some code warnings

A couple of fixes to satisfy the Eclipse static code analysis tool.
- Initialize all members in constructors
- Remove unused forward declarations
- Add parentheses when combining logical and bitwise operators
- Fix a case statement with no break (it was intentional)

Change-Id: Icecb8cc98c6f58b97ab33fffb621f0edc33a7d3c
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 3759a92..f4d6826 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -162,7 +162,7 @@
 
     struct DisplayDeviceState {
         DisplayDeviceState();
-        DisplayDeviceState(DisplayDevice::DisplayType type);
+        DisplayDeviceState(DisplayDevice::DisplayType type, bool isSecure);
         bool isValid() const { return type >= 0; }
         bool isMainDisplay() const { return type == DisplayDevice::DISPLAY_PRIMARY; }
         bool isVirtualDisplay() const { return type >= DisplayDevice::DISPLAY_VIRTUAL; }